Çok düşük frekanslı elektromanyetik alanların lenfositlerin membran potansiyellerine etkisi

Amaç: Çok düşük frekanslı elektromanyetik alanların (ÇDF-EMA) canlılar üzerinde olumlu ve olumsuz etkileri daha önce gösterilmekle beraber etki mekanizması henüz bilinmemektedir. Ancak bu etkileşimin hücrenin membranında meydana gelen bir değişimle gerçekleştiği düşünülmektedir. Bu çalışmanın amacı, düşük frekanslı elektromanyetik alan uygulanan mitojen ile indüklenmiş lenfositlerin membran potansiyellerinde meydana gelecek olası değişiklikleri floresans spektroskopisi yöntemi kullanılarak saptamak ve meydana gelen bu değişim ile hücre çoğalması arasındaki ilişkiyi belirlemektir Yöntem: Çalışmada sağlıklı insan kanından izole edilen T lenfositleri 72 saat RPMI-1640 içeren hücre kültür ortamında inkübe edilmişlerdir. Kontrol ve manyetik alan olmak üzere iki grup oluşturulmuştur. Hücreler 90 dakika manyetik alana maruz bırakıldıktan sonra membran potansiyel değişimini saptamak için di-4-ANNEPS probu kullanılarak floresans spektroskopik ölçümler yapılmıştır. Hücreler tripan mavisi ile boyandıktan sonra ışık mikroskopunda toma camında sayılmıştır. Bulgular ve Sonuç: Düşük frekanslı elektromanyetik alana maruz bırakılan lenfositlerin membran potansiyellerinde hiperpolarizasyon ve hücre sayılarında azalma meydana saptanmıştır. Bu bulgular ÇDF-EMA'nın membran potansiyelini ve hücre çoğalmasını etkilediğini göstermektedir.

The effect of extremly low frequency magnetic fields on membrane potential of lymphocytes

Aim: Although previous studies demonstrated that extremly low frequency magnetic fields (ELF-EMF) affected biologic systems the mechanisms has not been elucidated yet. However, it is accepted that the interaction must involve the physicochemical properties of the plasma membrane. This study aimed to determine the probable change in membrane potential of mitogen induced lymphocytes exposed to ELF-EMF and correlate it with changes in proliferation of exposed cells. Methods: Lymphocytes from healthy donors were grown in RPMI medium for 72 hours, before magnetic field ( 50 Hz, 5 mT) was applied for 90 minutes. Fluorescence spectroscopy with di-4-Anepps as a probe was used to determine change in membrane potential in the the magnetic field applied and control groups. Cell count was made with cytometer using trypan blue stain. Results: Fluorescence spectroscopy studies revealed that magnetic field applied lymphocytes showed hyperpolarization with respect to control. A decrease in proliferation was observed in ELF-EMF exposed cells with respect to controls. These findings indicate that ELF-EMF affects membrane potential and cell proliferation.

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